The health secretary has set out details of a massive new round of NHS building projects.

John Reid gave his backing on Tuesday to a series of projects across England valued at £4 billion.

But unions were angered by news that the schemes will largely be funded by the controversial private finance initiative.

Reid said that the latest announcement brings total spending on new hospitals to over £16 billion since Labour came to power in 1997.

The government is also on course to meet its target of 100 new hospital schemes open to patients by 2010.

Among the schemes to get the go ahead was a £204 million maternity and children's hospital in Leeds.

And Hillingdon Hospital in north west London will benefit from a £271 million redevelopment.

Modernisation

"The NHS is in the middle of the biggest hospital building programme in its history," said Reid.

"After years of under-investment, the infrastructure of the NHS is at last being modernised and made fit for the 21st century.

"The new hospital plans given the green light today represent the type of bright, modern, clean environments that all NHS patients should experience during their treatment.

"I look forward to seeing further progress on these schemes, and all of the other hospital building projects that are underway, and particularly to seeing the benefits they will bring to their local communities.

"I am delighted to receive such good quality proposals and I will be encouraging local health organisations to progress these rapidly through the next important stages of their development."

PFI

But the Liberal Democrats warned that the PFI contracts should be transparent and open.

"Spending on hospitals using PFI is to be welcomed if building is completed on time and on budget," said Treasury spokesman Dr Vince Cable.

"Many PFI contracts are entered into for the wrong reasons and often undertaken to keep borrowing costs off the balance books.

"PFI contracts are surrounded by secrecy and confidentiality clauses.

"It is essential that the government ensure that contracts are transparent so that we can judge whether they are good value."

Concerns about the PFI schemes were echoed by public sector union Unison.

General secretary Dave Prentis said the announcement was "great news for patients, bad news for taxpayers".

"PFI is still the only show in town and today big business will be cheering all the way to the bank," he added.

"The private sector is carving up this very lucrative PFI market despite wide ranging concerns that they are not good value for money."